I have a good friend,who is probably one of the smartest people I know,He is an aviation genious, He owns/maintains and flys a very impressive collection of aircraft. He introduced me to the world of Warbirds and I look up to him for alot of Knowledge, not all of it Aviation related. He believes wholeheartedly that the government is up to no good with the chemtrails. I have spent some time listening, but I just cant buy into it and I dont have the gumption to tell him he's a bit nuts...Here's some reading for ya...
http://www.anomalies-unlimited.com/Chemtrails.html

http://www.apfn.org/apfn/contrails.htm

http://www.coasttocoastam.com/